Connecter



pril 6, 1937.

' H. A: DOUGLAS CONNECTER Original Filed Dec. 22, 1932 ification.

Patented Apr. .6, 1937 UNITED STATES CONNECTER Harry A. Douglas, Bronson, Mich.

Application December 22, 1932, Serial No. 648,355 Renewed April 1, 1936 2 Claims.

This invention relates to connecters more particularly for electrical conductors.

Among other objects, the invention aims to provide an improved line connecter in which insulating coupling members maintain the conductors in engagement.

The invention is of particular utility when embodied in a test plug connecter for laboratory and test equipment.

Other objects and advantages will be apparent from the following description taken together with the accompanying drawing showing an illustrative embodimentl of the invention.

In the drawingu Figure 1 is a. longitudinal view of a connecter assembly incorporating my invention;

Figure 2 is a longitudinal section of the connecter shown in assembly in Figure 1, on a somewhat larger scale; i Figure 3 is a cross-section taken on the line 3-3 of Figure 2;

Figure 4 is a cross-section taken on the line Figure 5 is a fragmentary view showing a mod- In the illustrative construction, my improved connecter l includes a pair of electrical conductors here represented by the generally cylindrical metallic plug 2 and the metallic sleeve 3,

the latter being associated with a current conducting wire 4 having the usual insulation 5 thereon. 'I'he plug 2 at one end is axially recessed as at 6 and the plug is flared thereabouts as 'at 1 to provide an external annular shoulder.

The insulating coupling member 8 is also generally cylindrical and has a cylindrical bor 9 longitudinally therethroughwhich receives ethe plug 2. An internal formation such as the annular shoulder III in the bore of the member 8 40 abuts the are 1 of the plug to limit relative movement of the plug and coupling member 8 in one direction. The plug 2 may be inserted in the member 8 from the right hand end of the member as shown in Figure 2 until the shoulders l and I0 abut, the plug lbeing of sufficient length so that its end opposite the shoulder 'I then projects through the opposite end of the member 8 a suitable distance as shown, when the invention is used in the herein described specific exemplication.

The metallic sleeve 3 which forms a part of the other conductor here referred to is shown split longitudinally at one end to provide aplurality of, in this instance three, spring tongues II. At their free ends these tongues desirably carry radial enlargements I2. At its opposite end the sleeve 3 has a reduced extension I3. The wire 4 with its insulation 5 thereon is passed through the sleeve 3, the end of the wire being bared of its insulation and bentback over the reduced extension I3 as at I4. The extension I3 may be longitudinally grooved as by being depressed at I5 to receive the bent back end 4 of the wire.

Another insulating coupling member I6 has a bore I'I which receives the wire and sleeve 3, the wire being passed through the left hand end of the coupling and out the right hand end to be continued to a suitable source of electric current (not shown). The coupling member I6 has an internal formation adapted to abut the sleeve 3 to limit relative longitudinal movement of the sleeve and member I6, but in this instance this formation also acts as a cam surface to pressI the tongues I I radially into engagement with the insulation 5 to clamp the sleeve upon the insulation, the inner surfaces of the tongues II advantageously having teeth I8 thereon, formed for example by screw threading the interior of the sleeve, to bite into the insulation 5. For this purpose, the bore Il is here shown constructed as at, I9 to form an annular tapering surface upon which the enlargements I2 of the tongues II ride as the sleeve and coupling I6 are moved relatively longitudinally in one direction.

To interengage the conductors the extension I3 of the sleeve 3 is adapted to be received in the recess 6 of the plug 2, the bore 9 of the coupling member 8 being enlarged as at 20, to at this time receive the sleeve 3 itself therein. The end of the.coupling member 8 thus receiving the sleeve 3 is at the same time received in the bore I'I of the coupling member I6 annularly of the sleeve 3. The telescoping ends of the coupling members 8 and I6 are respectively exteriorly and interiorly threaded to provide the complementary screw threads 2|.. When the coupling members 8 and I6 are screwed together as shown, the plug 2 is held against relative movement with respect to the coupling member 8, while the sleeve 3 is forced axially oi' the plug 2 and coupling member 8 as far as the extension I3 will go into the recess 6 and normally until the wire 4 is clamped between the bottom wall. 22 of the recess I 6 and v'the extension I3. At the same time, since some relative movement between the sleeve 3 and coupling member I6 is permitted by the tapered surfaceV I9, the tongues II are forced radially into engagement with the insulation 5. Thus the farther the members 8 and I6 are screwed together Cil the tighter will be the engagement between the plug 2 and sleeve 3 and between the sleeve 3 and the wire 4.

The insulating coupling members 8 and I6 are deslrably formed'of moulded phenolic condensation product and are provided on their outer peripheries, respectively, with'knurlings 23 and 24, whereby they may be relatively rotated to be screwed together as described.

A tapered tip 25 may be formed on the exposed end of the plug 2 which may be readily inserted in a socket member 26 carried by an insulating panel 21 to make an electrical connection with another wire (not shown) which may be conf nected with another socket member 28 at the opposite side of the panel. The socket member 26 may have a cylindrical socket 29 therein extending axially thereof and a ball detent 30 may be pressed into this socket 29 by a resilient metal split-ring 3| carried by the socket member 26, the tip 25 of the plug 2 having an annular depression 32 therein into which the ball 3|] snaps to make a yielding but firm connection between the socket member 26 and the plug 2. The socket member 26 is more specifically described and.

claimed in my copending application, Serial No. 648,354 led December 22, 1932.

S constructed and arranged, the connecter l is especially adapted for laboratory or test work, since the plug 2 is in improved mechanical and electrical engagement with the wire 4 an-d the connecter may be quickly, but securely snapped successively into one after another of a number of sockets similar to the socket 26 carried by the panel 21. The insulating coupling members 8 and I6 together make a convenient handle for the plug 2 as well as an insulator therefor. When it is desired to pull the plug out of the socket, the wire 4 may be pulled upon without danger of disrupting its attachment to the connecter l, since the harder the wire is pulled upon, the tighter will the tongues H bevclamped upon the insulation 5. Thus the connecter is capable of withstanding great abuse and the severe and constant service required of a test plug connecter.

As shown in Figure 5, a plug 33 may be substituted for the plug 2 when a prod test plug is desired, that is one which merely is touched to another conductor. In this modiiication the plug 33 may have a simple conical tip 34 terminating in a somewhat sharp point 35.

Having described my invention, I claim:

l. An electrical conductor including a cylindrical metal plug having an axial recess at one end and that end being provided with an annular exterior shoulder, a metallic sleeve having a reduced extension slidably mounted within said plug recess and being counter-bored to receive an insulated electrical conductor and toallow the bared conductor to pass therethrough to engage the plug within said recess, the exterior portion of the sleeve being split longitudinally to form means to clamp the insulation of the conductor and terminating in an annular exterior shoulder, in combination with two threaded interlocking members of insulating material, one of said members being axially bored to receive the cylindrical plug and being counter-bored to receive said plug shoulder and sleeve mounted therein and the other of said members beingv axially bored to receive the insulated conductor, said bore decreasing in diameter toward the outer end for engaging and coacting with the sleeve shoulder as the said members are threaded one upon the other for wedging the split sleeve `upon the insulation of the conductor and clamping the conductor in engagement with the plug.

2. In combination: a body, including a pair of members each carrying means cooperable to effect connection of said members and each apertured to form a composite aperture extending longitudinally of said body; an electrical conductor member, having a part disposed within said composite aperture, and a part communicating with the exterior of said body; means disposed within said composite aperture, and having a part movable radially inwardly to grip a portion of an electrical conductor; said body members when connected acting on said means to urge said means toward said conductor member and hold the electrical conductor in position in electrical engagement with said conductor member; said body members being of insulating material.

HARRY A. DOUGLAS. 

